Bug #17629: macOS, readline compiled with libedit: adding entries to history doesn't work unless Readline.readline is called before populating it

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 3.1.0dev (2021-02-13T02:51:33Z master 813fe4c256) [arm64-darwin20]
• Backport: 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN

[radarek (Radosław Bułat)]

Description

If Ruby's readline extension is linked with libedit library and readline history is populated before Readline.readline method is called then items are not available via history navigation mechanism (up/down arrows).

How to reproduce

bug.rb (also attached to this issue)

require 'readline'

# calling below code before populating history will make it work
Readline.readline('press enter to continue', false) if ENV['WORKAROUND'] == '1'

Readline::HISTORY << 'Line1'
puts "History: #{Readline::HISTORY.to_a}"
Readline.readline('> ', true)

$ ~/opt/ruby/bin/ruby -v bug.rb
ruby 3.1.0dev (2021-02-13T02:51:33Z master 813fe4c256) [arm64-darwin20]
History: ["Line1"]
> # pressing up arrow doesn't show entries from history

$ WORKAROUND=1 ~/opt/ruby/bin/ruby -v bug.rb
ruby 3.1.0dev (2021-02-13T02:51:33Z master 813fe4c256) [arm64-darwin20]
press enter to continue
History: ["Line1"]
> Line1 # up arrow was pressed here and entry from history was shown up

Bug affects for example pry gem (history doesn't work).

My setup

macOS 11.2.1 Big Sur
architecture: arm64 (apple M1 processor)
ruby -v: ruby 3.1.0dev (2021-02-13T02:51:33Z master 813fe4c256) [arm64-darwin20]

readline extension linkage:
otool -L /Users/radarek/opt/ruby/lib/ruby/3.1.0/arm64-darwin20/readline.bundle
/Users/radarek/opt/ruby/lib/ruby/3.1.0/arm64-darwin20/readline.bundle:
	/usr/lib/libedit.3.dylib (compatibility version 2.0.0, current version 3.0.0)
	/usr/lib/libncurses.5.4.dylib (compatibility version 5.4.0, current version 5.4.0)
	/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current version 1292.60.1)

[radarek (Radosław Bułat)]

• File Dockerfile Dockerfile added

I added Dockerfile with instructions to build ruby with libedit library to reproduce this bug more easily.

docker docker build -t readline-bug . # run inside directory with Dockerfile and bug.rb files

To reproduce bug:

docker run --rm -it -v $PWD:/app readline-bug /opt/bin/ruby /app/bug.rb
docker run --rm -it -v $PWD:/app -e WORKAROUND=1 readline-bug /opt/bin/ruby /app/bug.rb

[nobu (Nobuyoshi Nakada)]

Seems libedit needs to be initialized before managing the history.

diff --git a/ext/readline/readline.c b/ext/readline/readline.c
index 9f76f90e41a..b804ae6ae24 100644
--- a/ext/readline/readline.c
+++ b/ext/readline/readline.c
@@ -2088,6 +2088,7 @@ Init_readline(void)
 #if defined HAVE_CLEAR_HISTORY || defined HAVE_REMOVE_HISTORY
     if (strncmp(rl_library_version, EDIT_LINE_LIBRARY_VERSION,
                 strlen(EDIT_LINE_LIBRARY_VERSION)) == 0) {
+        prepare_readline();
         add_history("1");
         if (history_get(history_get_offset_func(0)) == NULL) {
             history_get_offset_func = history_get_offset_0;

[radarek (Radosław Bułat)]

I believe this ticket can be closed as it is fixed in master branch. @nobu (Nobuyoshi Nakada), Thank you for fixing this!

[nobu (Nobuyoshi Nakada)]

• Backport changed from 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN to 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN

The auto close didn’t seem to work somehow.

[radarek (Radosław Bułat)]

Can someone close this ticket? I don't see a possibility to do it myself.

[jeremyevans0 (Jeremy Evans)]

• Status changed from Open to Closed